1. Field of Invention
This invention relates to crop harvesting machines of the type that use rotary cutters to sever standing crops from the field and then condition the cut crop between one or more sets of conditioner rolls before depositing the crop back onto the ground in the form of a windrow or swath, and more particularly to conditioner rolls powered with an auxiliary power drive.
2. Description of Related Art
Wide cut rotary harvesters present inherent challenges in getting outboard severed crop materials to flow smoothly and without hesitation in a lateral direction toward the center of the machine before then turning rearwardly and moving through a central discharge opening into the conditioner rolls. Hesitation on the part of the crop materials as they “turn the corner”’ and move rearwardly into the conditioner rolls can cause problems, both in the quality of the finished windrows and the quality of cutoff being achieved by the rotary cutters. Due to the increased speeds at which rotary harvesters can travel compared to that of sickle-type machines, cutoff, feeding and control problems are exacerbated in rotary machines due to the dramatically increased volume of cut material flowing through the machines.
In one rotary cutter bed design, a group of inboard cutters of the bed are arranged with their axes of rotation directly in front of the opening to the conditioner rolls, inboard of conditioning structure on the rolls. One or more additional outboard cutters may be provided at each end of the bed and have their axes of rotation located outboard of the opening and the conditioning structure. In some situations, some or all of the crop streams end up against the structure behind the outboard cutters.
The cut-of quality of rotary headers can be improved in certain conditions by reducing the rotational speed of the cutterbar. In addition, the power required to drive the cutterbar can often be reduced with slower speeds. With a hydrostatically driven header, this is accomplished by reducing the flow rate of oil in the drive system. However, this method of reducing header speed also reduces the maximum power potential of the hydrostatic system due to the reduced flow rate. This causes the hydraulic system pressure to increase and in extreme conditions can result in unstable header speed and the hydrostatic system exceeding the relief valve setting.
Another potential problem with typical rotary headers is that the power for the conditioner rolls is transmitted through a belt drive system. In heavy, bulky crops, this belt drive system can become the limiting factor for machine capacity as the conditioner rolls require a greater percentage of the total header power.
Based on the foregoing, it would be desirable to have a rotary header with improved means to power the conditioner rolls.